glgConvertTo_32 on the iPhone
I ran my app through Instruments today and noticed that an excessively high amount of time was being spent in the "glgConvertTo_32" function. I read elsewhere that this is because Apple uses "GL_BGRA and GL_UNSIGNED_INT_8_8_8_8_REV" for it's texture format, and my code uses GL_RGBA.
I'm using glTexture2D as follows:
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, textureData);
Neither GL_BGRA nor GL_UNSIGNED_INT_8_8_8_8_REV are available in the GL headers for iPhone, however. Is there another reason for the high volume of calls to that function, or is there possibly a different texture format I should be using?
EDIT:开发者_StackOverflow社区 I should mention that I'm using OpenGL ES 2.0.
I don't know if my problem/solution is really related to yours. But your unanswered question was the first result google found while investigating my problem.
Although I use OpenGL ES 1.1 and don't use Textures I also noticed that my app spends about 23% of time in the function glgConvertTo_32().
After changing the value of kEAGLDrawablePropertyColorFormat from kEAGLColorFormatRGBA8 to kEAGLColorFormatRGB565 in eaglLayer.drawableProperties the function glgConvertTo_32() is not called anymore. The app feels faster and I don't see a visual difference.
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